# define _CRT_SECURE_NO_WARNINGS
# include <stdio.h>
int main() 
{
	int year = 0;
	int month = 0;
	printf("please input the year and the month:");
	scanf("%d %d",&year,&month);
	switch (month)
	{
	case 1:
	case 3:
	case 5:
	case 7:
	case 8:
	case 10:
	case 12 :
		printf("the month has 31 days.");
		break;
	case 4:
	case 6:
	case 9:
	case 11:
		printf("the month has 30 days.");
		break;
	default:
((year % 4 == 0) && (year % 100 != 0) || (year % 400 == 0) )? printf("the month has 29 days."):printf("the month has 28 days.");
		break;
	}
	return 0;
}
